Abstract：The purpose of the research is to analyze and evaluate the biomechanical capability of bioabsorbable scaffolds during processing and clinical application. Based onfinite element method, hexahedron mesh models were generated. Scaffolds and mock vessels were assumed to be isotropic incompressible materials, with constitutive models of elastoplasticity and hyperelasticity, respectively. Boundary and contact conditions were applied in the basis of practical processing and clinical applications. The Implicit solver of finite element software Abaqus were utilized to simulate the performance of three specific bioabsorbable scaffolds,B-2508, B-3018, and B-3528, under loadings for crimping, dilation, post-dilation and fatigue. The results were demonstrated. During crimping, the peak stress values for scaffold B-2508, B-3018, and B-3528 were 55.47, 55.47, and 50.51 MPa respectively. During dilation, the peak stress values were 64.10, 66.09, and 66.25 MPa respectively. During post-dilation, the peak stress values were 66.10, 65.85, and 67.85 MPa respectively. In high-cycle fatigue graph, all coordinates of mean stress-alternate stress for B-2508 and B-3018 were below the fatigue-critical line 1, while coordinates of a few nodes for B-3528 were above the fatigue-critical line 1. In summary, B-3528 was the best for crimping safety, B-2508 was the best for dilation safety, and B-3018 was the best for fatigue safety. Based on this study, an accurate simulation analytical method of biomechanical capability for bioabsorbable scaffolds were provided, and a theoretical instruction were conducted for product development of bioabsorbable-scaffold-like devices and precise clinical operations.
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